A Curious Equation
by pekori
Summary: Kaoru is suffering from something he can't quite describe, something new and unpleasant.  Hikaru can't even help, though, for somehow he ended up being the catalyst. [First in a trilogy.]


Author's Note: This is a standalone piece that is also part of a trilogy. It is part one of three. This, along with its companion pieces, combine to form a beginning, middle and end of something deeply tragic, but not without its light at the end of the tunnel. I dare not give too much away because I'd much rather have you read it and find out for yourselves. As always, I hope you enjoy (and everyone loves reviews kthx). 

Disclaimer and Acknowledgements: _Ouran High School Host Club_ was created by Bisco Hatori and definitely not licensed by myself. Therefore, the following is a work of fiction using characters that are not my own, and no harm nor profit is meant or made by publishing this.

* * *

The best part about being a twin is that you are never alone in the world. 

The worst part about being a twin is that you are never alone in the world.

The absolute dichotomy of these expressions was something that had lingered on Kaoru's mind for quite some time now: Ever since he first realized his twin's feelings for Haruhi were slowly but surely beginning to overshadow his feelings for his other half. For the first time in his life, he felt a pang in his chest that was completely new to him. He could remember the scene quite distinctly. He and Hikaru were at home, each working on their math lessons, and somewhere amidst all of inequalities Hikaru had been reminded of Haruhi and, naturally, brought her up.

"I was sort of impressed today with Haruhi."

Kaoru made no sound, but stopped his pencil and turned to look at Hikaru.

"The way that she didn't even flinch during the competition."

Oh. That. Now Kaoru could understand where Haruhi factored into their math homework — no pun intended. Sensei had split the class into teams and they had competed for an opportunity to skip their lessons tonight. Clearly the twins had been on a losing team, but that was only because no one stood a chance against Haruhi. Every equation she was given, she solved faster than anyone in the room. The twins had only been marginally disappointed when they were assigned a team other than hers, but by the end of the competition they were utterly defeated.

"That was pretty impressive of her, wasn't it?"

Hikaru gave a little nod and a smile to Kaoru. Kaoru told himself that it was just the glimmer of his unrealized feelings for Haruhi in his eyes that blinded Hikaru from noticing the slight sadness in his twin's. And that was when the pang had struck. It was dull and brief, but it was there. And it _hurt_. And Kaoru still now had no idea what it was. It bothered him through the rest of their homework and through dinner, through bedtime routines and even as he was trying to sleep that night. The only thought that distracted him at all, just once, was a bit of slight relief that tomorrow was Sunday, which meant no classes, which meant no sleep wouldn't affect him too harshly.

Morning came, and Kaoru's eyes had only ever fallen shut when he was trying to force himself to sleep. Even with the drapes drawn, he could tell the sun was rising by the way their backlighting became brighter and brighter as the minutes ticked by. It wasn't the sunrise that he was waiting on, rather for Hikaru to finally awaken so that he might have something better to distract himself with. Something more potent.

When his twin stirred, Kaoru jumped a little, nervous until he realized he was being watched. "Good morning, Kaoru." His voice was sleepy, but pleasant, and Kaoru was glad because it was familiar. "When did you wake up?"

"In time to see the sunrise." It wasn't a lie, he told himself. That was one thing he couldn't do to Hikaru: lie to him.

Hikaru sat up immediately, his face showing his concern despite Kaoru's meek attempt to dissuade it. "And you aren't tired? Why didn't you wake me? We could have watched it together." There was a slight pout to his expression also, Kaoru noticed. It was good to see it; it made him feel a bit more whole because he knew that he would have felt just as cheated had Hikaru stayed up without waking him.

"I couldn't bring myself to do it. You looked too peaceful."

But Hikaru was looking at the curtains, now, and when he turned back to Kaoru, his face was puzzled. "How did you watch the sunrise with the drapes closed?"

Kaoru laughed, but it was flat and Hikaru noticed; he could tell from the slight twinge he had upon hearing it. "Hikaru, you're being stupid. Come on. Let's go get breakfast. Aren't we meeting up with Haruhi today?"

That brightened Hikaru's face. That name. And there was that pain in his chest again and this time Kaoru winced a little from it. Thankfully, Hikaru had already turned to get out of bed when it happened, so he hadn't caught sight of it. Somehow, though, that made it hurt even worse and Kaoru had some difficulty suppressing the urge to clutch at his chest because of it.

As they sat at breakfast, Hikaru still took no other notice that something was overwhelming his other half. Naturally, that only compounded the issue, so much so that long after Hikaru finished eating, Kaoru was still feeling much too sick to even lift an arm.

"Kaoru..." Finally, he took notice, and Kaoru weakly turned to look at him. Hikaru didn't say another word, but everything was in his expression. Kaoru only shook his head in response, and that was when Hikaru got angry.

"What do you mean, no! All I have is you and all you have is me! There is no no!"

"That isn't true, Hikaru."

"Don't say that! Don't—" Hikaru stopped himself, calming a bit before continuing but not yet realizing the severity of his shouting. Not yet realizing that this was the first true argument they were having. "Come on. We'll finish breakfast and then we can call Haruhi—"

"You've already finished and I'm not hungry. I'm just going to stay home today. I'm not feeling well."

"I fell for this trick last time, Kaoru. It isn't going to work again."

"Hikaru, I'm truly not feeling well."

"I won't leave without you."

Again, Kaoru only shook his head but this time with a bit more of a smile. Hikaru's obstinance reminded him of all the times throughout their young lives when they had taken advantage of the opportunity to cause some mischief. From their parents' parties to all the awful things they'd done to kids at school to making Tamaki crazy with jealousy during the host club—

Jealous. That was it. Kaoru's eyes widened with his own realization and while he heard Hikaru's pleads as a dull roar, he didn't acknowledge them. Then, still disregarding what his twin was saying, Kaoru said plainly, "I want you to go have fun with Haruhi today."

"I want us _both_ to have fun with Haruhi today. What fun is it at all if you aren't there?"

"You've been out with just her before and you had a great time. Why is this any different?"

"Because! It just is..." Hikaru's voice was defeated and confused, matching the expression that marred his face, only intensifying the feelings building in Kaoru's gut that things were just so different now. Too different.

Kaoru stood, Hikaru having jumped to his feet in outrage just before his shouting, and set his hands on either side of his twin's face. His look immediately softened, but still didn't quite mirror Kaoru's properly, being riddled with so much anxiety and perplexion. "It's okay. I'm feeling tired and I need to sleep and I don't want to ruin your plans. Go have fun."

"Kaoru..." It was such a strange turn of events to hear Hikaru speak his name like that, with a tone precisely like the tone he himself took during their host club duties. He was always the submissive; he didn't know that there was any room for dominance in him.

"I will be here when you get back. Wake me up when you do?" He offered his other half a small grin, secret and just for him. It implied nothing and everything all at once and while Hikaru didn't like the situation, he finally truly understood. He could only give a half-hearted nod in reply, and mustered a bit of a smile for Kaoru in return before he turned to go get ready to leave.

Feeling drained and uneasy, Kaoru went to slink back into his chair when Hikaru suddenly took him up in his arms, pulling him in an embrace closer than any they had maybe ever shared. Kaoru was thrown at first, but quickly sunk into it, nestling himself gently and warmly and holding onto his twin as if they'd never see each other again. But that was impossible for them, so he knew he had no reason to worry. They both knew.

"I won't be long."

"No, no. Please. I didn't sleep at all last night and I could really use the rest."

"What? Kaoru..."

"Hikaru. Go. She's waiting." And very gently, Kaoru placed a kiss on his brother's lips. It was something they hadn't shared in ages, and lately only ever teased at for the girls, but this felt like the right time to use it once more. Hikaru said nothing, but Kaoru was fairly certain he felt a slight return in his action, and that was when he truly turned to leave his twin to go on what was now to be a second date with Haruhi.

This time Kaoru ignored his chair completely, left his untouched breakfast where it was and made his way back upstairs to their shared bedroom. The bed was empty without Hikaru there with him and that only made it even more difficult to fall asleep, despite his growing fatigue. But soon, Kaoru did manage to finally drift off, but not before Hikaru said a few more goodbyes and Kaoru mumbled something sleepily in reply.

* * *

_Fin._


End file.
